Estimating the difference worksheet for rounding whole numbers to nearest ten and hundred.

To solve the problem, we need to estimate the difference between each pair of numbers by rounding them to the nearest ten and the nearest hundred. Let's go through each question step by step.

Step 1: Understand Rounding Rules

- Nearest Ten: Look at the ones place. If it is 5 or greater, round up; otherwise, round down.
- Nearest Hundred: Look at the tens place. If it is 5 or greater, round up; otherwise, round down.

Step 2: Solve Each Question

#### Question 1: \( 273 - 145 \)

1. Round to Nearest Ten:
- \( 273 \): The ones digit is 3 (less than 5), so round down to 270.
- \( 145 \): The ones digit is 5 (equal to 5), so round up to 150.
- Estimated difference: \( 270 - 150 = 120 \).

2. Round to Nearest Hundred:
- \( 273 \): The tens digit is 7 (greater than 5), so round up to 300.
- \( 145 \): The tens digit is 4 (less than 5), so round down to 100.
- Estimated difference: \( 300 - 100 = 200 \).

#### Question 2: \( 687 - 521 \)

1. Round to Nearest Ten:
- \( 687 \): The ones digit is 7 (greater than 5), so round up to 690.
- \( 521 \): The ones digit is 1 (less than 5), so round down to 520.
- Estimated difference: \( 690 - 520 = 170 \).

2. Round to Nearest Hundred:
- \( 687 \): The tens digit is 8 (greater than 5), so round up to 700.
- \( 521 \): The tens digit is 2 (less than 5), so round down to 500.
- Estimated difference: \( 700 - 500 = 200 \).

#### Question 3: \( 479 - 156 \)

1. Round to Nearest Ten:
- \( 479 \): The ones digit is 9 (greater than 5), so round up to 480.
- \( 156 \): The ones digit is 6 (greater than 5), so round up to 160.
- Estimated difference: \( 480 - 160 = 320 \).

2. Round to Nearest Hundred:
- \( 479 \): The tens digit is 7 (greater than 5), so round up to 500.
- \( 156 \): The tens digit is 5 (equal to 5), so round up to 200.
- Estimated difference: \( 500 - 200 = 300 \).

#### Question 4: \( 872 - 365 \)

1. Round to Nearest Ten:
- \( 872 \): The ones digit is 2 (less than 5), so round down to 870.
- \( 365 \): The ones digit is 5 (equal to 5), so round up to 370.
- Estimated difference: \( 870 - 370 = 500 \).

2. Round to Nearest Hundred:
- \( 872 \): The tens digit is 7 (greater than 5), so round up to 900.
- \( 365 \): The tens digit is 6 (greater than 5), so round up to 400.
- Estimated difference: \( 900 - 400 = 500 \).

#### Question 5: \( 698 - 324 \)

1. Round to Nearest Ten:
- \( 698 \): The ones digit is 8 (greater than 5), so round up to 700.
- \( 324 \): The ones digit is 4 (less than 5), so round down to 320.
- Estimated difference: \( 700 - 320 = 380 \).

2. Round to Nearest Hundred:
- \( 698 \): The tens digit is 9 (greater than 5), so round up to 700.
- \( 324 \): The tens digit is 2 (less than 5), so round down to 300.
- Estimated difference: \( 700 - 300 = 400 \).

Final Answer

| Question | Nearest Ten | Nearest Hundred |
|----------------|-------------|-----------------|
| \( 273 - 145 \) | 120 | 200 |
| \( 687 - 521 \) | 170 | 200 |
| \( 479 - 156 \) | 320 | 300 |
| \( 872 - 365 \) | 500 | 500 |
| \( 698 - 324 \) | 380 | 400 |

$$
\boxed{
\begin{array}{|c|c|c|}
\hline
\text{Question} & \text{Nearest Ten} & \text{Nearest Hundred} \\
\hline
273 - 145 & 120 & 200 \\
687 - 521 & 170 & 200 \\
479 - 156 & 320 & 300 \\
872 - 365 & 500 & 500 \\
698 - 324 & 380 & 400 \\
\hline
\end{array}
}
$$